A week ago I built a FusionHub on a $5 server at Digital Ocean. It works well.
I used this image https://download.peplink.com/firmware/fusionhub/fusionhub-do.vmdk which I got from this thread FusionHub - Installation in Digital Ocean - #18 by MartinLangmaid.
I’m not sure how I would have found that image directly. It doesn’t seem to be here https://www.peplink.com/support/downloads/